unable to load metadata in XAML Design mode

Question

I signed the assemblies of two library projects. Now, in a WPF application project, the XAML designer is saying there is a "problem loading".  The project compiles and runs ok. Just the XAML designer is complaining.  What could the problem be?

here is the error message:
Unable to load the metadata for assembly 'SharpLib'. This assembly may have been downloaded
from the web.  See http://go.microsoft.com/fwlink/?LinkId=179545.  The following error was encountered
during load: Could not load file or assembly
'SharpLib, Version=1.0.0.0, Culture=neutral, PublicKeyToken=xxxxx28445e56ee' or one of its
 dependencies. The located assembly's manifest definition does not match the assembly reference.
 (Exception from HRESULT: 0x80131040) 

thanks,

Answer 1

It got better by itself.  Probably closing the solution and then reopening it later.